Hello together,
we are running into a problem with TelerikPdfViewer. When clicking the download button, download starts and performs properly.
BUT: the downloaded PDF file does not match the PDF that was provided via Data="@PdfData". On download something internally prepends some text to the PDF:
–€À³JS.ReceiveByteArray’Æ ‘¢%PDF-1.7 %úûüý 3 0 obj <</ca 1.00000 /AIS false >> endobj 5 0 obj
The original PDF file starts at "%PDF-1.7" (end of first line). That part before (including that "JS.ReceiveByteArray") was somehow added during the download workflow by Telerik. We ensured that the PDF data we provided to the viewer (via Data="@PdfData") ist valid. We did so by inspecting the byte[]-Array manually in the debugger as well as downloading it via a JS function to the client.
This is how we are using the TelerikPdfViewer. But the error occurs no matter if we are handling the OnDownload-Event (setting the filename) or not handlign that event at all (i.e. eliminating the OnDownload="@OnPdfDownload" completely)
<TelerikPdfViewer Data="@PdfData" Width="100%" Height="100%" Zoom="1m" OnDownload="@OnPdfDownload">
<PdfViewerToolBar>
<PdfViewerToolBarPagerTool />
<PdfViewerToolBarSpacer />
<PdfViewerToolBarZoomTool />
<PdfViewerToolBarSelectionTool />
<PdfViewerToolBarSearchTool />
<PdfViewerToolBarSpacer />
<PdfViewerToolBarDownloadTool />
<PdfViewerToolBarPrintTool />
</PdfViewerToolBar>
</TelerikPdfViewer>We use Telerik.UI.for.Blazor (6.2.0).
Thanks for your feedback on this issue and best regards!
Sebastian
@Nadezhda Tacheva
Hi Nadezhda,
yes, I can confirm that this looks like the bug I am expirencing. I opened the PDF document linked in that other bug report in a text editor (Notepad++) and was able to verify that the same chunk of bytes is prepended to the PDF's actual content:
The PDF can be opened in browsers and in Adobe Acrobat without any issue. But other programs fail (such as applications to digitally sign that PDF - e.g. DigiSeal). Furthermore other actions / checks cannot be performed anymore (e.g. checking that a PDF file was not altered), as the file is already changed when downloading it for the first time.
Best regards
Sebastian